Shady balcony

(Question)

I think it’s just wishful thinking, but hoping you may have an answer. I live in an apartment so only containers for me. I am looking for Zone 5 plants with the following:
– perennial if possible
– do well in shade (direct sun only from 9 am – 1 pm)
– do well in containers (I can go up to 16″ pots max.)
– fragrance and color (big deal for me)
– long flowering season (limited space, no room for variety)
– bonus if you can also recommend vines

I realize I am asking for a lot. I love roses but seriously doubt they would tolerate this much shade, even though my balcony is very bright. I am fortunate enough to have bees and cardinals visit me and I enjoy my balcony. I hope to enjoy it even more with your help.

Thanks!
Arlene

(Answer)

Your wishes can come true (at least to some extent!) in your balcony garden. Container gardening on a balcony does have some challenges of its own, including shade, drought, wind, and weight restrictions, but it is possible to achieve a beautiful and serene space that checks off most of your list.

Perennials can pose a challenge in a container on a balcony or on a deck, because they are often not hardy enough to survive a winter of repeated freezing and thawing – what is known as the freeze/thaw cycle that is typical of Toronto’s winter climate. The rule of thumb for overwintering perennials in containers in Zone 5 is that the plants should be hardy to at two zones lower. Even still, in a severe winter they may succumb.

For a successful container balcony garden, a mix of different types of plants might be the best way to achieve your wish list, even if you do have to do a little experimenting from year to year. Here are some ideas for you to consider as a starting point:

Perennial grasses: these can form the backbone of a few of your containers. A reliable container grass – in all seasons because its lovely seed heads are beautiful in the winter too – is the ever popular and easy to find Feather Reed Grass: https://www.bluestem.ca/calamagrostis-karl-foerster.htm

To fill in your containers with beautiful foliage and flowers, two perennials to try are: Tiarella Cordifolia (foam flower) and Geraniummacrorrhizum (cranesbill geranium). They are both hardy to zone 3, and will tolerate shade and dry conditions. Both have scent: the leaves of the cranesbill are lemony, and the flowers of the Tiarella are lightly scented. Hostas are hardy to zone 2 – choose a smaller variety, or even a mini-hosta: https://carolynsshadegardens.com/2017/05/18/fun-with-mini-hostas-in-containers/

If you’d like something that trails, you could use some of the many inexpensive annual plants that are easy to come by at many nurseries: sweet potato vine (either lime green, “Margarita” or burgundy, “Sweet Caroline Raven”) or white or pink Bacopa with its tiny leaves and flowers, or any ivy.

Herbs are fantastic in balcony containers for their foliage, the scent, their flowers, and their general usefulness. Some, like chives and thyme, will often overwinter in a container and come back reliably the following spring. Others, like rosemary, oregano and sage, are a little more tender, but can last until well into the cold weather. Many varieties of mint have lovely flowers that really attract pollinators. Even those herbs known to love full sun will usually give you a season of good picking. Some balcony gardeners bring their herbs inside for the winter; others leave them by the balcony door and use them through the early part of the winter.

Vines are well worth attempting in a sheltered spot on the balcony. The hardy kiwi, Actinidia arguta ‘Issai’ for example, which we are seeing more frequently even in big box garden centres, is hardy to zone 4 and can be grown in a container, where its growth can be curtailed. Some Clematis varieties, hardy to zone 4, such as “Miss Bateman” are considered suitable for containers – this variety can climb or trail.

Many balcony gardeners choose miniature roses, which are readily available and reliable bloomers: they perform best with a minimum of 6 hours of sun per day, but if you are willing to experiment, you may find you have success.

There are plenty of colourful annuals to choose from to add a splash of colour on your balcony. Many garden centres tag their annuals helpfully with a “partial shade” symbol, but if a sun-loving striped petunia appeals to you, you should just go for it and hopefully it will give you a good display through the summer months. Coleus is a fantastic container plant for colourful, interesting foliage: https://www.finegardening.com/article/4-ways-to-design-with-coleus

Choosing the right containers is important for balcony gardeners. Pots made of clay or porcelain will likely not survive a winter on the balcony. Those made of plastic, or resin composites, metal or wood will be fine outside all winter, and many will be lighter in weight.

Cultural practices to note: When your perennials stop growing in the fall, they will still need regular watering when the soil dries out. If you have been adding a fertilizer, stop in the fall and then resume again in the spring when your perennials begin to grow again. Good drainage is also important for your plants to thrive, as is the right growing medium: a lightweight mix formulated for containers is best.